<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        img {
            vertical-align: middle;
        }
        div {
            position: relative;
            float: left;
            margin: 40px;
        }
        div:hover::before{
            content:" ";
            position: absolute;
            width: 100%;
            height: 100%;
            top: 0;
            left: 0;
            border:10px solid rgba(255,255,255,.4);
            box-sizing: border-box;          
        }
    </style>
</head>
<body>
    <div>
        <img src="ll.jpg" alt="" width="400">
    </div>
<br>
    <div>
        <img src="ll.jpg" alt="" width="300">
    </div>
    <br>
    <div>
        <img src="ll.jpg" alt="" width="200">
    </div>  
    <br>
    <div>
        <img src="ll.jpg" alt="" width="100">
    </div>     
</body>
</html>